Test circuits and test systems

Abstract

The embodiment of the present invention discloses a test circuit and a test system. Through an input end, an output end and a current generating circuit in the test circuit, based on the input end receiving an input voltage provided by a signal generator, the output end is connected to a power supply to be tested, the current generating circuit generates a simulated working current of a target module, and the simulated working current is applied to the output end of the power supply to be tested through the output end. Thus, the test environment of different current change rates of the power supply to be tested is simulated by the current generating circuit, so that the dynamic response capabilities of different power supply schemes can be verified, and the reliability and accuracy of the evaluation of the power supply scheme can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to a test circuit and a test system. Background Art

[0002] As the demand for high current, low voltage power supplies in electronic devices and systems increases, especially in the fields of artificial intelligence, data centers, electric vehicles, and high-performance computing, the dynamic response performance of power supplies has become particularly important. In these applications, the power ripple when the current changes dynamically needs to be strictly controlled.

[0003] In the prior art, the performance of the power supply when the current changes dynamically is generally tested by using a power load meter with a customized power cable and connector. However, the current slope provided by the existing power load meter is relatively low and is far from meeting these high-demand application scenarios. In addition, the parasitic inductance introduced by the customized cable will further limit the current slope, affecting the reliability and accuracy of the test results. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a test circuit and a test system, whereby a current generating circuit is used to simulate a test environment with different current change rates of a power supply to be tested, thereby verifying the dynamic response capabilities of different power supply schemes and improving the reliability and accuracy of the evaluation of the power supply schemes.

[0005] In a first aspect, an embodiment of the present invention provides a test circuit, wherein the test circuit comprises:

[0006] An input terminal, connected to the signal generator and configured to receive an input voltage provided by the signal generator;

[0007] Output terminal, connected to the power supply to be tested;

[0008] At least one current generating circuit is located between the input terminal and the output terminal, and is configured to generate an analog operating current of a target module according to the input voltage, and apply the analog operating current to the output terminal of the power supply under test through the output terminal.

[0009] In some embodiments, the test circuit further comprises:

[0010] A voltage follower is connected to the signal generator and is used to isolate the signal generator from the current generating circuit.

[0011] In some embodiments, the test circuit further comprises:

[0012] A protection circuit is connected to the current generating circuit and the voltage follower, and is used for overcurrent protection of the current generating circuit.

[0013] In some embodiments, the protection circuit comprises:

[0014] A comparator, whose output end is connected to the control end of the voltage follower;

[0015] A first resistor, connected between a reference current source and an inverting input terminal of the comparator, for obtaining a reference current;

[0016] The second resistor is connected between the non-inverting input terminal of the comparator and the current generating circuit, and is used to obtain the feedback current.

[0017] In some embodiments, in response to the feedback current being greater than the reference current, the comparator outputs a high level to control the voltage follower to shut down; in response to the feedback current being less than or equal to the reference current, the comparator outputs a low level to control the voltage follower to operate normally.

[0018] In some embodiments, the current generating circuit comprises:

[0019] A first operational amplifier, a non-inverting input terminal of which is connected to the output terminal of the voltage follower;

[0020] A first switch tube, a control end of which is connected to the output end of the operational amplifier;

[0021] a third resistor connected between the ground terminal and the inverting input terminal of the operational amplifier;

[0022] A fourth resistor is connected in series with the first switch tube between the output terminal and the ground terminal;

[0023] a fifth resistor, connected between a common end of the fourth resistor and the first switch tube and an inverting input end of the operational amplifier;

[0024] A sixth resistor is connected between the non-inverting input terminal of the operational amplifier and the ground terminal.

[0025] In some embodiments, the current generating circuit further comprises:

[0026] A parallel component connected between the output terminal and the inverting input terminal of the operational amplifier;

[0027] Wherein, the parallel component includes a first capacitor and a seventh resistor connected in parallel.

[0028] In some embodiments, the current generating circuit further comprises:

[0029] An eighth resistor is connected between the control terminal of the first switch tube and the ground terminal.

[0030] In some embodiments, there are multiple current generating circuits, and the multiple current generating circuits are connected in parallel.

[0031] In a second aspect, an embodiment of the present invention provides a testing system, the system comprising:

[0032] The power supply to be tested;

[0033] Signal generator;

[0034] Oscilloscope;

[0035] A test circuit as described in the first aspect.

[0036] The technical solution of the embodiment of the present invention is to have an input terminal, an output terminal and a current generating circuit in the test circuit, based on the input terminal receiving the input voltage provided by the signal generator, connect the output terminal to the power supply to be tested, generate the simulated working current of the target module through the current generating circuit, and apply the simulated working current to the output terminal of the power supply to be tested through the output terminal. Thus, the test environment of different current change rates of the power supply to be tested is simulated by the current generating circuit, so that the dynamic response capabilities of different power supply schemes can be verified, and the reliability and accuracy of the evaluation of the power supply scheme can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0038] Figure 1 is a schematic diagram of a test system according to an embodiment of the present invention;

[0039] Figure 2 is a schematic diagram of a test circuit according to an embodiment of the present invention;

[0040] Figure 3 is a circuit diagram of a test circuit according to an embodiment of the present invention;

[0041] Figure 4 is a schematic diagram of a test circuit according to another embodiment of the present invention. DETAILED DESCRIPTION

[0042] The present application is described below based on embodiments, but the present application is not limited to these embodiments. In the detailed description of the present application below, some specific details are described in detail. It is possible for those skilled in the art to fully understand the present application without the description of these details. In order to avoid confusing the essence of the present application, known methods, processes, flows, components and circuits are not described in detail.

[0043] In addition, persons of ordinary skill in the art will appreciate that the drawings provided herein are for illustration purposes and are not necessarily drawn to scale.

[0044] At the same time, it should be understood that in the following description, "circuit" refers to a conductive loop composed of at least one element or subcircuit through electrical connection or electromagnetic connection. When an element or circuit is said to be "connected to" another element or an element / circuit is said to be "connected between" two nodes, it can be directly coupled or connected to another element or there can be an intermediate element, and the connection between the elements can be physical, logical, or a combination thereof. On the contrary, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there is no intermediate element between the two.

[0045] Unless the context clearly requires otherwise, the words "include", "comprising" and similar words throughout the application should be interpreted as including rather than exclusive or exhaustive; that is, the meaning is "including but not limited to".

[0046] In the description of this application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0047] With the development of artificial intelligence, people's demand for data, computing power and algorithms is becoming more and more urgent. In order to meet the above needs, a large number of high-precision computing power cards are needed. High-precision computing power cards are professional hardware devices that integrate advanced computing technology. They use high-performance computing units and high-speed data transmission interfaces. They are designed to meet the needs of complex application scenarios such as high-performance computing, deep learning, data analysis, graphics rendering and cloud computing. This type of computing power card has powerful computing capabilities and can handle large-scale data sets and complex algorithms. It also has good scalability and flexibility. By applying high-precision computing power cards, users can significantly improve the computing efficiency and response speed of the system, and accelerate the data processing and model training process.

[0048] At present, high-precision computing power cards are gradually developing in the direction of high current and low voltage. At the same time, the requirements of high-precision computing power cards for power supply ripple during dynamic current changes will also increase accordingly. Therefore, the requirements of high-precision computing power cards for power supply manufacturers are also correspondingly increased, especially the dynamic response part of the power module.

[0049] In order to find a power solution that can better meet the power supply requirements of high-precision computing power cards, high-precision computing power card designers will design dynamic load boards to evaluate the pros and cons of power solutions from different power supply manufacturers, especially the pros and cons of the dynamic response performance of power modules. A dynamic load board is a highly flexible and powerful test device or circuit board that has the ability to automatically adjust or simulate load changes according to actual application scenarios and test requirements. Dynamic load boards are usually designed for power supply testing, electronic system verification, performance evaluation, and reliability testing. In many fields, to ensure that the system under test can maintain stable performance and reliability under various load conditions. By using a dynamic load board, the performance of the power supply or electronic system can be more effectively evaluated and optimized, thereby accelerating the product development cycle, reducing production costs, and improving product quality.

[0050] Among them, the current slope is a parameter that can intuitively reflect the power demand capacity of the high-precision computing power card. Therefore, in the test process of the high-precision computing power card, the dynamic load board, as a device for simulating the high-precision computing power card, needs to be able to simulate all current slopes when the high-precision computing power card is working. However, the current slope that can be provided by the power load meter method adopted in the existing technical solution is relatively small and cannot meet the use requirements in the above application scenarios. Therefore, the dynamic load board needs a solution that can simulate the maximum current slope when the high-precision computing power card is working, so as to realize the simulation of the current under various working conditions of the high-precision computing power card.

[0051] Figure 1 Schematic diagram of a test system according to an embodiment of the present invention. Figure 1 As shown, the test system includes a power supply to be tested 1, a signal generator 2, a test circuit 3, and an oscilloscope 4.

[0052] The power supply 1 to be tested is the power supply that needs to be tested. Specifically, it is necessary to test the size of the power ripple of the power supply 1 to be tested at different current slopes, so as to judge the quality of the power supply 1 to be tested according to the size of the power ripple. Among them, the power ripple is the phenomenon that the AC component is superimposed on the output voltage of the DC stable power supply. The power ripple causes the DC voltage that should be a fixed value to fluctuate. Excessive power ripple may cause unstable operation of the device and even interfere with the normal operation of the device.

[0053] The signal generator 2 is used to provide an input voltage. In the embodiment of the present invention, the input voltage provided by the signal generator 2 varies with time, thereby simulating the working state of the high-precision computing power card to test the power supply 1 to be tested. The working principle of the signal generator 2 is to generate a low-frequency sinusoidal oscillation signal, which is then amplified by a voltage amplifier to meet the voltage output amplitude requirement, and then directly outputs the voltage through an output attenuator. At the same time, the output voltage can be adjusted by the main oscillation output adjustment potentiometer.

[0054] The test circuit 3 is connected to the signal generator 2 and the power supply 1 to be tested, and is configured to receive the input voltage of the signal generator 2 at the input end to generate a simulated working current I of the simulated high-precision computing power card. t , the simulated working current I t The current slope has a certain value and will simulate the working current I t It is applied to the power supply 1 to be tested, thereby realizing the simulation of the influence of currents with different current slopes on the power ripple of the power supply 1 to be tested when the high-precision computing power card is working.

[0055] The oscilloscope 4 is connected to both ends of the power supply 1 to be tested, and is configured to display the power ripple of the power supply 1 to be tested at different current slopes. The tester determines the power ripple of the power supply 1 to be tested at different current slopes by observing the waveform changes of the oscilloscope 4, and determines the quality of the power supply to be tested based on the power ripple. The basic working principle of the oscilloscope is to capture and display the transient waveform of the electrical signal. The oscilloscope can capture and display the dynamic changes of the signal in real time, helping the tester to intuitively understand the key parameters of the signal, such as the frequency, amplitude, phase, period, and noise and distortion in the signal. Specifically, the larger the power ripple of the power supply 1 to be tested, the worse the quality of the power supply to be tested, and the smaller the power ripple of the power supply to be tested, the better the quality of the power supply to be tested.

[0056] Figure 2 is a schematic diagram of a test circuit according to an embodiment of the present invention, such as Figure 2 As shown, the dotted box is a schematic diagram of the test circuit 3, and the dotted box is a schematic diagram of other components of the test system, wherein the test circuit 3 includes an input terminal P1, an output terminal P2, a voltage follower 31, a protection circuit 32 and a current generating circuit 33.

[0057] The input terminal P1 is connected to the signal generator 2 and is configured to receive the input voltage V0 provided by the signal generator 2 .

[0058] The output terminal P2 is connected to the power supply 1 to be tested, and is used to provide a simulated working current I to the power supply 1 to be tested. t .

[0059] The voltage follower 31 is connected to the signal generator 2, and is used to output a voltage of the same magnitude at its output terminal according to the voltage at the in-phase input terminal. In the embodiment of the present invention, the voltage follower 31 is used to isolate the signal generator 2 and the current generating circuit 33. Due to the high input impedance characteristics of the voltage follower 31, the influence of external noise on the current generating circuit 33 can be reduced, thereby effectively improving the anti-interference ability of the system and ensuring the accuracy and reliability of the signal.

[0060] The protection circuit 32 is connected to the current generating circuit 33 and the voltage follower 31, and is used to perform overcurrent protection on the current generating circuit 33. Specifically, when the current value of the current generating circuit 33 is greater than a predetermined value, the voltage follower 31 is controlled to be turned off so that no current flows through the current generating circuit 33, thereby playing a protective role for the current generating circuit 33.

[0061] The current generating circuit 33 is connected to the voltage follower 31 and the output terminal P2, and is configured to generate an analog operating current I of the target module according to the input voltage V0. t , and the simulated working current I t The target module is specifically a high-precision computing power card, so it is necessary to generate a simulated working current I when the high-precision computing power card is working. t .

[0062] In the embodiment of the present invention, an input terminal, an output terminal and a current generating circuit are arranged in the test circuit, based on the input terminal receiving the input voltage provided by the signal generator, the output terminal is connected to the power supply to be tested, the analog working current of the target module is generated by the current generating circuit, and the analog working current is applied to the output terminal of the power supply to be tested through the output terminal. Thus, the test environment of different current change rates of the power supply to be tested is simulated by the current generating circuit, so that the dynamic response capabilities of different power supply schemes can be verified, and the reliability and accuracy of the evaluation of the power supply scheme can be improved.

[0063] Figure 3 is a circuit diagram of a test circuit according to an embodiment of the present invention, such as Figure 3 As shown, the test circuit includes an input terminal P1, an output terminal P2, a voltage follower 31, a protection circuit 32 and a current generating circuit 33.

[0064] The voltage follower 31 includes a second operational amplifier OP2 and a feedback circuit. The feedback circuit includes a resistor R', the in-phase input terminal of the second operational amplifier OP2 is connected to the input terminal P1, and the inverting input terminal is connected to the output terminal through the resistor R'. According to the amplification principle of the operational amplifier, the amplification factor of the second operational amplifier OP2 is 1+R' / R in , R in is the input impedance of the inverting input terminal. According to the principle of virtual disconnection, the inverting input terminal is in an open circuit state, so the input impedance of the inverting input terminal is R inThe output voltage of the second operational amplifier OP2 is equal to the voltage V0 of the non-inverting input terminal, thereby achieving the effect of voltage following. The voltage follower can improve the matching of the input impedance and output impedance of the circuit and reduce the load effect of the signal source. Due to its high input impedance and low output impedance, the voltage follower can effectively reduce the current consumption of the signal source and isolate the front and rear stage circuits to reduce mutual influence.

[0065] The protection circuit 32 includes a comparator CMP, a first resistor R1 and a second resistor R2, wherein the output terminal of the comparator CMP is connected to the control terminal (ctrl) of the voltage follower 31 to control the on or off of the voltage follower. The first resistor R1 is connected between the reference current source and the inverting input terminal of the comparator CMP to provide a reference current I to the inverting input terminal of the comparator CMP. ref The second resistor R2 is connected between the non-inverting input terminal of the comparator CMP and the current generating circuit 33, and is used to obtain the feedback current I fb , the feedback current I fb Used to characterize the current situation of the current generating circuit. Specifically, the feedback current I fb Equal to the analog working current I t The comparator CMP is configured to output a high level in response to the voltage at the non-inverting input terminal being greater than the inverting input terminal, and to output a low level in response to the voltage at the non-inverting input terminal being less than or equal to the inverting input terminal. The voltage follower 31 is configured to be turned off when the control terminal is at a high level, and to be turned on when the control terminal is at a low level. Specifically, in some embodiments, when the feedback current I fb Greater than the reference current I ref , indicating that the current in the current generating circuit 33 is relatively large, and there may be a dangerous situation. At this time, the comparator CMP outputs a high level, controls the voltage follower 31 to turn off, and there is no current in the current generating circuit 33, thereby realizing the protection of the current generating circuit 33. When the feedback current I fb Less than or equal to the reference current I ref , indicating that the current in the current generating circuit 33 is relatively small and there is no danger. At this time, the comparator CMP outputs a low level and controls the voltage follower 31 to work normally.

[0066] The current generating circuit 33 includes a first operational amplifier OP1, a first switch tube Q1, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first capacitor C1, a seventh resistor R7 and an eighth resistor R8. The current generating circuit 33 is connected to the voltage follower 31 via a protection resistor R0.

[0067] The non-inverting input terminal of the first operational amplifier OP1 is connected to the output terminal of the voltage follower 31 to obtain the output voltage V1 of the voltage follower 31, and the third resistor R3 is connected between the ground terminal and the inverting input terminal of the first operational amplifier OP1, wherein the voltage of the common terminal a3 of the third resistor R3 and the inverting input terminal of the first operational amplifier OP1 is equal to the voltage of the inverting input terminal of the operational amplifier.

[0068] The fourth resistor R4 and the first switch tube Q1 are connected in series between the ground terminal and the output terminal P2, wherein the fourth resistor R4 is close to the ground terminal and the first switch tube Q1 is close to the output terminal P2. The control terminal of the first switch tube Q1 is connected to the output terminal of the first operational amplifier OP1 to control the first switch tube Q1 to be turned on or off according to the voltage output by the output terminal of the first operational amplifier OP1. In some embodiments, the first switch tube Q1 is implemented by NMOS (Negative channel-Metal-Oxide-Semiconductor, N-type metal oxide semiconductor), including a source, a gate and a drain, wherein the gate is connected to the output terminal of the first operational amplifier OP1, the drain is connected to the output terminal P2, and the source is connected to the fourth resistor R4. Specifically, when the gate voltage of the first switch tube Q1 is greater than a predetermined value, the first switch tube Q1 is turned on. In an embodiment of the present invention, when the signal generator 2 provides an input voltage, the voltage at the output terminal of the first operational amplifier OP1 controls the conduction state of the first switch tube Q1. After the first switch tube Q1 is turned on, the analog working current I on the fourth resistor R4 t The analog working current I flowing through the fourth resistor R4 is output to the output terminal P2 for testing the power supply 1 to be tested. t The current slope is predetermined, so that the power supply 1 to be tested is tested at the predetermined current slope.

[0069] The fifth resistor R5 is connected between the node a4 and the inverting input terminal of the first operational amplifier OP1, wherein the node a4 is the common terminal of the fourth resistor R4 and the first switch tube Q1. The sixth resistor R6 is connected between the non-inverting input terminal of the first operational amplifier OP1 and the ground terminal. The two ends of the fifth resistor R5 are respectively the node a3 and the node a4, and the two ends of the sixth resistor R6 are respectively the node a2 and the node a5.

[0070] In some embodiments, the test circuit further includes a seventh resistor R7 and a first capacitor C1, wherein the seventh resistor R7 and the first capacitor C1 are connected in parallel between the output terminal and the inverting input terminal of the first operational amplifier OP1 to form a resistor and capacitor parallel component. By setting the parallel component, on the one hand, the output oscillation of the first operational amplifier OP1 can be prevented, and interference can be coupled to the output terminal of the first operational amplifier OP1 to avoid erroneous switching of the first switch tube Q1, and on the other hand, the output signal of the output terminal of the first operational amplifier OP1 can be filtered and the frequency cutoff can be performed.

[0071] In some embodiments, the test circuit also includes an eighth resistor R8, which is connected between the control end and the ground end of the first switch tube Q1. The eighth resistor R8 is used to provide a discharge path for the charge accumulated in the gate of the first switch tube Q1, thereby preventing the first switch tube Q1 from being abnormally turned on. At the same time, it can also accelerate the shutdown of the first switch tube Q1.

[0072] Regarding the voltages of the nodes in the figure, the voltage at node a1 is set to V1, the voltage at node a2 is set to V2, the voltage at node a3 is set to V3, the voltage at node a4 is set to V4, and the voltage at node a5 is set to V5. It should be noted that the second resistor R2 is connected between the non-inverting input terminal of the comparator CMP and the current generating circuit 33. Specifically, the second resistor R2 is connected to the node a4. The comparator CMP obtains the feedback current I of the node a4. fb , and the feedback current I fb With reference current I ref For comparison, when the current of the current generating circuit 33 is too large, the voltage follower 31 is turned off to protect the current generating circuit 33, wherein the feedback current I fb The value is equal to the simulated working current I t .

[0073] Next, the simulated working current I flowing through the fourth resistor R4 is t Specifically, according to the principle of virtual short of the first operational amplifier OP1, the current flowing through the protection resistor R0 and the current flowing through the sixth resistor R6 are equal, so the following formula can be obtained based on this relationship:

[0074]

[0075] Similarly, the current flowing through the third resistor R3 is equal to the current flowing through the fifth resistor R5, so the following formula can be obtained based on this relationship:

[0076]

[0077] According to the virtual short principle of the first operational amplifier OP1, the voltage at point a3 is equal to the voltage at point a2, that is:

[0078] V2=V3

[0079] For the convenience of calculation, set R0 = R6 = R5 = R3, and combine V2 = V3 to get the following formula:

[0080] V1=V4-V5

[0081] According to the principle that the output voltage of the voltage follower 31 and the voltage of the in-phase input terminal are the same, the following formula can be obtained:

[0082] V1=V0

[0083] Therefore, the voltage relationship is: V0 = V4-V5, that is, the voltage across the fourth resistor R4 is equal to the input voltage V0 provided by the signal generator 2, and since the value of the fourth resistor R4 is fixed, the analog working current I flowing through the fourth resistor R4 is t It is proportional to the input voltage V0 provided by the signal generator. From the above analysis, it can be concluded that when the voltage slope of the input voltage of the signal generator 2 is adjusted, the analog working current I flowing through the fourth resistor R4 t It also has a corresponding current slope and is provided to P2 through the first switch tube Q1. Therefore, the analog working current I with different current slopes can be generated by changing the voltage slope output by the signal generator 2. t For testing the power supply 1 under test.

[0084] A specific example is given below to illustrate that the voltage slope of the input voltage V0 provided by the signal generator 2 is 1000V / us, and the resistance value of the fourth resistor R4 is 5Ω. Then the analog working current I provided by the current generating circuit 33 to the output terminal P2 is t The current slope is the ratio of the voltage slope of the input voltage V0 to the fourth resistor R4, specifically 200A / us, and is applied to the power supply 1 to be tested to implement the test of the power supply 1 to be tested. When it is necessary to simulate current slopes of other magnitudes, the voltage slope of the input voltage provided by the control signal generator 2 can be changed accordingly. For example, when it is necessary to simulate a current slope of 300A / us, the voltage slope of the input voltage V0 provided by the control signal generator 2 is changed to 1500V / us.

[0085] In some embodiments, it is necessary to generate a higher current slope analog operating current I t , using a current generating circuit 33 to provide an analog working current I tIt is difficult to achieve, therefore, it is necessary to improve on the basis of this embodiment to generate a simulated working current I with a higher current slope. t .

[0086] Figure 4 is a schematic diagram of a test circuit according to another embodiment of the present invention. Figure 4 As shown, the test circuit includes a plurality of current generating circuits 33, which are connected in parallel and share a fourth resistor R4. Each current generating circuit 33 receives an input voltage from a signal generator 2 and outputs a simulated working current I t Since the multiple current generating circuits 33 are connected in parallel, the analog working current I output by each current generating circuit 33 is t is superimposed on the fourth resistor R4, so that the total analog working current I ta The current slope is also equal to the respective analog working current I t The sum of the current slopes.

[0087] The following is an example. The voltage slope of the input voltage provided by the signal generator is 1000V / us, the resistance of the fourth resistor R4 is 5Ω, and there are ten current generating circuits 33 connected in parallel. Then, the analog working current I provided by each current generating circuit 33 is t The current slope is 200A / us, and the simulated working current I of the ten current generating circuits 33 superimposed on R4 ta The current slope is 2000A / us. Therefore, by connecting a plurality of current generating circuits 33 in parallel, the current slope of the simulated working current is improved, thereby achieving the simulation of a larger current slope based on the limited input signal provided by the signal generator. In other words, if the current slope to be simulated is higher, the number of current generating circuits 33 connected in parallel can be further increased to achieve the improvement of the current slope.

[0088] The embodiment of the present invention includes an input terminal, an output terminal and a current generating circuit in a test circuit, receives an input voltage provided by a signal generator based on the input terminal, connects to the power supply to be tested through the output terminal, generates a simulated working current of the target module through the current generating circuit, and applies the simulated working current to the output terminal of the power supply to be tested through the output terminal. Thus, the test environment of different current change rates of the power supply to be tested is simulated by the current generating circuit, so that the dynamic response capabilities of different power supply schemes can be verified, and the reliability and accuracy of the evaluation of the power supply scheme can be improved.

[0089] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A test circuit, characterized in that: The test circuit comprises: An input terminal, connected to the signal generator and configured to receive an input voltage provided by the signal generator; Output terminal, connected to the power supply to be tested; At least one current generating circuit is located between the input terminal and the output terminal, and is configured to generate an analog operating current according to the input voltage, and apply the analog operating current to the power supply under test through the output terminal.

2. The test circuit according to claim 1, characterized in that: The test circuit further comprises: A voltage follower is connected to the signal generator at the input end and is used to isolate the signal generator from the current generating circuit.

3. The test circuit according to claim 2, characterized in that: The test circuit further comprises: A protection circuit is connected to the current generating circuit and the voltage follower respectively, and is used for overcurrent protection of the current generating circuit.

4. The test circuit according to claim 3, characterized in that: The protection circuit comprises: A comparator, whose output end is connected to the control end of the voltage follower; A first resistor, connected between a reference current source and an inverting input terminal of the comparator, for obtaining a reference current; The second resistor is connected between the non-inverting input terminal of the comparator and the current generating circuit, and is used to obtain the feedback current.

5. The test circuit according to claim 4, characterized in that: In response to the feedback current being greater than the reference current, the comparator outputs a high level to control the voltage follower to shut down; in response to the feedback current being less than or equal to the reference current, the comparator outputs a low level to control the voltage follower to operate normally.

6. The test circuit according to claim 2, characterized in that: The current generating circuit comprises: A first operational amplifier, a non-inverting input terminal of which is connected to the output terminal of the voltage follower; A first switch tube, a control end of which is connected to the output end of the operational amplifier; a third resistor connected between the ground terminal and the inverting input terminal of the operational amplifier; A fourth resistor is connected in series with the first switch tube between the output terminal and the ground terminal; a fifth resistor, connected to the inverting input terminal of the operational amplifier between the fourth resistor and the common terminal of the first switch tube; A sixth resistor is connected between the non-inverting input terminal of the operational amplifier and the ground terminal.

7. The test circuit according to claim 6, characterized in that: The current generating circuit further comprises: A parallel component connected between the output terminal and the inverting input terminal of the operational amplifier; Wherein, the parallel component includes a first capacitor and a seventh resistor connected in parallel.

8. The test circuit according to claim 6, characterized in that: The current generating circuit further comprises: An eighth resistor is connected between the control terminal of the first switch tube and the ground terminal.

9. The test circuit according to claim 1, characterized in that: There are multiple current generating circuits, and the multiple current generating circuits are connected in parallel.

10. A testing system, characterized in that: The system comprises: The power supply to be tested; Signal generator; Oscilloscope; A test circuit as claimed in any one of claims 1 to 9.

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